Vibrator mounting



Nov. 11,1958 P. l. FETTINGER 2,860,290

VIBRATOR MOUNTING Filed Sept. 1, 1954 INVENTOR 717124 [72/1 /1152]" ATTORNEY United States Patent VIBRATOR MOUNTING Paul I. Fettinger, Indianapolis, Ind., assignor to P. R. Mallory & Co., Inc., Indianapolis, Ind., a corporation of Delaware Application September 1, 1954, Serial No. 453,661

8 Claims. (Cl. 317-182) This invention relates to mountings for electromagnetic vibratory interrupters, and, more particularly, to a sound reducing vibrator mounting of novel and im proved character.

Conventional vibrators are generally enclosed in a suitable can or casing closed at one end by a disc of insulating material carrying a plurality of contact prongs which are electrically connected to the vibrator. As the vibrator produces an appreciable amount of undesirable sound during its operation, provision has to be made to prevent or to reduce the transfer of such sound from the vibrator to the can or container. This is generally accomplished by interposing supporting members or mountings in the form of suitably shaped bodies of elastic material, such as of sponge rubber, between the coil and stack ends of the vibrator and the corresponding surfaces of the container or can. Although structures of the described character have reduced the radiation of vibrator sound or noise to a certain extent, their effectiveness was subject to great limitations and further reduction of the sound radiated constituted a serious problem in the vibrator art for many years.

I have discovered that the outstanding problem may be solved in a remarkably simple manner.

It is an object of the present invention to improve vibrator mountings.

' It is another object of the present invention to provide a novel and improved vibrator mounting which is capable of reducing the amount of sound transmitted from the vibrator to the container or can to an extent heretofore impossible.

'It is a further object of the invention to provide an improved vibrator mounting in which a relatively long path of vibration-absorbing elastic material is interposed between one end, such as the coil end, of the vibrator and the inner surface of the container, such path being effective in reducing the transfer of sound or noise to the container to a minimum.

The invention also contemplates an improved vibrator mounting characterized by a high compliance and excellent sound-absorbing characteristics which is simple in construction and which may be readily manufac tured and sold on a practical and industrial scale at a low cost.

Other and further objects and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawing, in which:

' Fig. l is a vertical sectional view of a vibrator having the novel mounting of the invention incorporated therein; and

Fig. 2 is a perspective view, having parts broken away for clarity of illustration, of the vibrator mounting of the invention.

The sound produced by a vibrator consists of a band of frequencies beginning with the basic vibrator frequency and extending to above 8000 cycles. In order to prevent the generated sound from leaving the container I pliant for the mass of the mechanism.

7 2,860,290 Patented Nov. 11, 1958 or can, it is essential that there be stages of mechanical filtering between the vibrator mechanism and the container. The mountings of the invention are essentially band elimination filters. A mechanical filter of this type is made up of masses and compliances in their correct relationship to filter out the sound. I have discovered that the failure of conventional vibrator mountings to provide a sufiicient amount of attenuation was due to the fact that the supporting medium between the vibrator and the container was never sufficiently com- In accordance with the principles of the present invention, I provide a supporting member formed of elastic material having a cup portion adapted to grip one end, preferably the coil end, of the vibrator and a skirt portion extending in the opposite direction from the open end of the cup portion into contacting position at its end with the container. I have found that a mounting of the described character, which may be considered to function as a long folded lever, achieves the required high compliance because the path of the support has been made considerably longer than heretofore possible due to the long folded lever action. A suitable bottom support of sponge rubber or similar elastic material is provided between the other end, for example, the stack end, of the vibrator and the container. While the bottom support may have a variety of different forms, it is preferably so designed as to have a maximum diameter slightly smaller than the inside diameter of the container. A small area of the compliant material is in contact with the container in any given position. This small area forms a supporting structure having greater compliance than heretofore obtainable. The light contact pressure obtained by this construction greatly reduces the transmission of high frequency vibrations from the vibrator to the container. High frequency vibrations are prevented from following the flexible lead wires to the outside by virtue of the fact that they are damped between the vibrator mechanism base and the rubber mounting.

Although, in the foregoing, mass and compliance have been considered as lumped constants, it must be remembered that the compliant medium of the support, such as rubber, itself has mass. By making the supporting rubber path long, this part acts as a series of filters with a distributed mass of rubber and compliance throughout its length, which constitutes an effective high frequency filter.

Referring now to the drawing, reference numeral 10 generally denotes a vibrator comprising a hook-shaped ferromagnetic frame 11, the hook end 12 of which constitutes a pole piece having a driver coil 13 around the same. The other end of the frame carries a stack generally denoted by numeral 14. In the said stack are spacedly clamped a pair of side arms 15 carrying relatively stationary contacts 16 at their free ends. Between the side arms 15 is spacedly clamped one end of a reed 17, the free end of which carries an armature 18 which extends into cooperating position with pole piece 12. A pair of compliant reed arms 19 are riveted to the two sides of reed 17 and carry at their ends vibratory contacts 20. Insulative spacers 21 are arranged between the frame, the side arms and the reed in order to electrically insulate them from each other. The stack itself is held together by means of a conventional bolt 22 and nut 23. An insulative sleeve (not shown) is provided around the bolt in the conventional manner in order to prevent short-circuiting the clamped metal parts by means of the bolt.

The vibrator just described is inserted into a metal container or can 24, the open end of which is constricted, as shown at 25, and holds an insulating base 26 between the said constricted portion and the crimped end 27 of the container. Contact prongs 28 are provided in base 26 and are electrically connected to the several elements of the vibrator by means of flexible lead wires 29.

The lowerer stack end of the vibrator is surrounded by an elastic'niountingiiil made of sponge rnbberor some other suitable elastic material. It will'be noted'inFig. 1 that mounting St) is provided with an inner space 31 accommodating the stack end of the vibrator andthat the lead wires 29'extend through the said mounting to the upperlend of prongs 2%. Mounting fail -is of such dimensions'as to have its maximum diameter sl' #13 smaller than the inside diameter of the container so that only a small area of the compliant material is in contact with the container in any given position, such area constituting a highly compliant support for that end of the vibrator.

The other or coil end of the vibrator is held by means of the mounting member of the invention, which is generally denoted by numeral 32. This member comprises a cup portion 33, which is of such dimensions as to grip the coil end of the vibrator. From the lower extremity of cup portion 33 extends a skirt portion 34 in the opposite direction and being to some extent divergent from the cup portion. The upper end of skirt portion 34 extends into contact with the inner surface of container 24, as shown at 35. An opening 36 may be provided in the center of cup portion 33.

As it will be best observed in Fig. 2, the novel mounting member of the invention is preferably provided in the form of a rotation body consisting of cylindrical or coni cal sections joined to form an integral cup and skirt. This structure provides a folded lever action as Well as a relatively long path between the coil end of the vibrator and the container. This long vibration-absorbing path is characterized by an extremely high compliance and is capable of reducing the transfer of sound from the vibrator to the container to an extent which was heretofore impossible. A further advantage of the novel vibrato-r. mounting of the invention is that it can be readily manufactured by molding or other similar operations from rubber or other elastomers at a cost which is not higher than that of manufacturing conventional vibrator mountings.

Although the present invention has been disclosed in connection with a preferred embodiment thereof, variations and modifications may be resorted to by those skilled in the art Without departing from the principles of the present invention. All of these variations and modifications are considered to be within the true spirit and scope of the present invention as disclosed in the foregoing description and defined by the appended claims.

I claim:

1. A vibrator assembly comprising, in combination, a container, a vibrator in said container, a supporting member formed of elastic material having a cup portion adapted to grip one end of the vibrator and a folded back skirt portion extending from the open end of, the cup portion to, the container with its end engaging the container adjacent the closed end of said cup, and resilient means for supporting the other end of the vibrator in said container.

2. A vibrator assembly comprising, in combinatioman' elongated container, a vibrator in said container, a sup-' porting member integrally formed of elastic material having a cup portion gripping one end of the vibrator and a skirt portion surrounding said cup extending in the -opposite direction from the open end of the cup portion elastic material having a cup portion gripping one end of the vibrator by its inner surface and a skirt portion integrally formed with said cup portion extending rearwardly from the open end of the cup portion into contacting position with said container at its end, said skirt surrounding said cup, and elastic means for holding the other end of the vibrator with respect to said container, said cup and skirt portions of the supporting member providing a folded lever action and a long vibration-absorbing path of high compliance between the gripped end of the vi-f brater the container, thereby effectively reducing the transfer of noise from the vibrator to the container.

4. A vibrator assembly comprising, in combination, an elongated container open at one end, a base held in said end of the container, a vibrator Within said container and spaced therefrom, a supporting member of elastic material interposed between one end of the vibrator and the container, said member having a cup portion internally gripping said end of the vibrator and a skirt portion integrally. 7

formed with said cup portion extending rearwardly in divergent direction from the open end of the cup portion into contacting position at its end with said container, said skirt being placed about said cup, and elastic means for holding the other end of the vibrator with respect to the base end of said container, said cup and skirt portions of the supporting member providing a folded lever action and a long vibration-absorbing path of high compliance between the gripped end of the vibrator and the container, thereby effectively reducing the transfer of sound from the vibrator to the container.

5. A vibrator assembly comprising, in combination, an elongated can open at one end, a base having contact prongs therein in said end ofthe can, a vibrator electrically connected to said prongs located within said canand spaced therefrom, a supporting member of elastic material interposed between the coil end of the vibrator and the can, said member having a cup portion internally gripping said end of the vibrator and a skirt portion integrally formed with said cup portion extending rearwardly and divergently from the open end of the cup portion into contacting position at its end with said can,

3. A vibrator assembly comprising, in combination, an 7 elongated container, a vibrator in said container, a supporting member in the form of a rotation body made of said skirt surrounding said cup, and elastic means for holding the stack end of the vibrator with respect to the base end of said can, said cup and skirt portions of the supporting member providing a folded lever actionand a long vibration-absorbing path 'of high compliance between the gripped end of the vibrator and the can, thereby effectively reducing the transfer of sound from' the vibrator to the can.

6. In combination with a vibrator assembly comprising a container, a vibrator in said container and spaced therefrom, and elastic means supporting one end of the vibrator with respect to the container; a supporting mem ber of elastic material interposed between the other end of the vibrator and the container, said member having, a cup portion internally gripping said end of the vibrator and a skirt portion extending rearwardly and divergently from the open end of the cup portion into contacting position at its end with said container, said skirt surrounding said cup, said cup and skirt portions of the supporting member providing a folded lever action and a long vibration-absorbing path of high compliance between the gripped end of the vibrator and the container, thereby effectively reducing the transfer of sound from the vibrator to the container.

7. A supporting member for vibrator assembliesformed of elastic material comprising a cup portion, and a skirt portion extending rearwardly from the open end of said cup portion, said cup portion being adapted to internally grip one end of a vibrator and the free edge of said skirt portion being adapted to adjacently contact the'inner suiface of a vibrator container.

8. A supporting member for vibrator assemblies integrally formed of elastic material comprising acupportion, and a skirt portion extending rearwardly and di-r,

vergently from the open end of the cup portion, said member being adapted to be interposed between one end of a vibrator and a container with said cup portion internally gripping the vibrator and the free edge of said skirt portion adjacently contacting the inner surface of said container, the cup and skirt portions of the member jointly constituting a long vibration-absorbing path effectively reducing the transfer of sound from the vibrator to the container.

References Cited in the file of this patent UNITED STATES PATENTS Nulsen Jan. 23, 1940 Slater Feb. 20, 1940 Aust Jan. 25, 1944 Aust Aug. 22, 1950 Huetten July 1, 1952 

